Table 1.
Characteristics of the four combination groups of maternal age and parity (n = 1193).
| Group A |
Group B |
Group C |
Group D |
P-value | |||||
|---|---|---|---|---|---|---|---|---|---|
| ≥ 35 and primiparous |
≥ 35 and multiparous |
< 35 and primiparous |
< 35 and multiparous |
||||||
| n = 284 | n = 268 | n = 432 | n = 209 | ||||||
| Maternal age, years | 37.7 ± 2.3 | 38.0 ± 2.5 | 29.6 ± 3.4 | 31.1 ± 2.8 | < 0.001 | ||||
| Prepregnancy BMI, kg/m2 | 20.4 ± 2.4 | 20.4 ± 2.4 | 19.7 ± 2.5 | 20.1 ± 2.7 | 0.001 | ||||
| < 18.5, n (%) | 50 | (17.6) | 45 | (16.8) | 136 | (31.5) | 51 | (24.4) | < 0.001 |
| 18.5–24.9, n (%) | 218 | (76.8) | 209 | (78.0) | 280 | (64.8) | 149 | (71.3) | |
| ≥ 25.0, n (%) | 16 | (5.6) | 14 | (5.2) | 16 | (3.7) | 9 | (4.3) | |
| Gestational weight gain, kilograms | 10.2 ± 3.6 | 10.1 ± 3.2 | 10.9 ± 3.4 | 10.1 ± 3.5 | 0.002 | ||||
| < 7.5, n (%) | 58 | (20.4) | 43 | (16.0) | 56 | (13.0) | 44 | (21.1) | 0.024 |
| 7.5–13.0, n (%) | 178 | (62.7) | 182 | (67.9) | 278 | (64.4) | 129 | (61.7) | |
| > 13.0, n (%) | 48 | (16.9) | 43 | (16.0) | 98 | (22.7) | 36 | (17.2) | |
| Pregnancy complications | |||||||||
| Pregnancy induced hypertension, n (%) | 18 | (6.3) | 5 | (1.9) | 13 | (3.0) | 1 | (0.5) | 0.001 |
| Gestational diabetes mellitus, n (%) | 16 | (5.6) | 8 | (3.0) | 6 | (1.4) | 5 | (2.4) | 0.011 |
| Maternal underlying disease, n (%) | 58 | (20.4) | 36 | (13.4) | 59 | (13.7) | 22 | (10.5) | 0.011 |
| Maternal lifestyle | |||||||||
| Cigarette smoking habit, n (%) | 67 | (23.6) | 39 | (14.6) | 89 | (20.6) | 33 | (15.8) | 0.024 |
| Alcohol drinking habit⁎, n (%) | 72 | (25.6) | 50 | (18.7) | 102 | (23.7) | 31 | (14.9) | 0.013 |
| Gestational week at delivery, weeks | 39.5 ± 1.1 | 39.3 ± 1.0 | 39.4 ± 1.0 | 39.1 ± 0.92 | < 0.001 | ||||
| 37, n (%) | 8 | (2.8) | 13 | (4.9) | 17 | (3.9) | 12 | (5.7) | < 0.001 |
| 38, n (%) | 41 | (14.4) | 50 | (18.7) | 59 | (13.7) | 38 | (18.2) | |
| 39, n (%) | 90 | (31.7) | 86 | (32.1) | 140 | (32.4) | 95 | (45.5) | |
| 40, n (%) | 91 | (32.0) | 96 | (35.8) | 154 | (35.6) | 55 | (26.3) | |
| 41–42, n (%) | 54 | (19.0) | 23 | (8.6) | 62 | (14.4) | 9 | (4.3) | |
| Child | |||||||||
| Males, n (%) | 156 | (54.9) | 136 | (50.7) | 204 | (47.2) | 107 | (51.2) | 0.248 |
| Birth weight, g | 3090 ± 309 | 3164 ± 347 | 3057 ± 304 | 3095 ± 317 | < 0.001 | ||||
| Nurturing support by grandparents⁎, n (%) | |||||||||
| No | 40 | 14.7 | 46 | 18.5 | 36 | 8.6 | 18 | 9.0 | 0.001 |
⁎
Missing: alcohol drinking (n = 6), support by grandparents (n = 51).